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Midair Collision over Denver

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Re: Midair Collision over Denver

#71

Post by akouri »

dmix wrote: post #42
nickcw wrote: post #7

Just in case anyone (like me) is thinking - wait did that aeroplane have a parachute? From: https://en.m.wikipedia.org/wiki/Cirrus_Airframe_Parachute_Sy... The Cirrus Airframe Parachute System (CAPS) is a whole-plane ballistic parachute recovery system designed specifically for Cirrus Aircraft's line of general aviation light aircraft including the SR20, SR22 and SF50. The design became the first of its kind to becom…

> The device is attributed with saving over 200 lives to date. https://www.cirruspilots.org/Safety/CAPS-Event-History

The SR-22 also cannot recover from a spin. I would assume most of those deployments are from out of control spins. I am not sure the parachute system can be credited for saving more lives than a similar plane not-equipped, because the Cirrus _needed_ that parachute system in order to be certified.

Re: Midair Collision over Denver

#72

Post by Aeolun »

goodcanadian wrote: post #65
ordu wrote: post #28

Earlier quoted context omitted.

The pilot is speaking about failed engine after the collision, like it is nothing. Fascinating. I'd be shouting something obscene in such a situation. For half an hour at least, I think.

He might not have been aware of the full extent of the damage. He is on final; the plane is flying; he's lost an engine; he's going to land it. There is no time for anything else.

I think it’s amazing planes can fly sort of straight with only one engine providing thrust though.

Re: Midair Collision over Denver

#73

Post by sokoloff »

akouri wrote: post #71
dmix wrote: post #42

Earlier quoted context omitted.

> The device is attributed with saving over 200 lives to date. https://www.cirruspilots.org/Safety/CAPS-Event-History

The SR-22 also cannot recover from a spin. I would assume most of those deployments are from out of control spins. I am not sure the parachute system can be credited for saving more lives than a similar plane not-equipped, because the Cirrus _needed_ that parachute system in order to be certified.

> The SR-22 also cannot recover from a spin.

The SR-22 can recover from a spin, using conventional anti-spin control inputs. EASA testing showed that.

It is true that Cirrus secured an “equivalent level of safety” ruling during FAA certification and so did not demonstrate conforming spin recovery in flight testing here, but it can recover.

Re: Midair Collision over Denver

#76

Post by mannykannot »

sokoloff wrote: post #58
dmix wrote: post #42

Earlier quoted context omitted.

> The device is attributed with saving over 200 lives to date. https://www.cirruspilots.org/Safety/CAPS-Event-History

That particular phrasing and calculation, suggesting that every chute deployment without fatalities represents that number of people “saved” is quite controversial and IMO not supported by an analysis of the data. I think it’s great that the system exists, it has undoubtedly saved lives, but unless Cirrus crashes are overwhelmingly fatal compared to other airplanes, it’s overstating “fatal accidents turned into non-f…

I completely agree, but for a more complete analysis, we would have to consider the fatality rate for the sort of crashes in which CAPS is employed.

IIRC, Cirrus is now encouraging pilots to use CAPS in any engine failure with sufficient altitude for it to work, on account of the number of such accidents, in CAPS-equipped aircraft, where the pilot chose not to use it, and someone aboard was killed or seriously injured. This will presumably further muddy the used/saved ratio, while probably increasing the total number of saved.

In a collision situation, at least one as violent as this one, you can't be sure whether some vital control or structure has been damaged to the point where it is about to fail, so using a parachute of any sort, where feasible, seems to be the rational choice.

Quite by accident, I came across this pucker-inducing article a couple of days ago, where thre's little doubt that bailing out, if it were an option, would have been the right thing to do, even though this flight ended safely in this case.

https://airfactsjournal.com/2019/03/student-flight-control-j...

(On second thoughts, if the pilot had a parachute, he could have attempted to free up the controls without making his situation any worse.)

Re: Midair Collision over Denver

#77

Post by marcinzm »

alister wrote: post #66
nickcw wrote: post #7

Just in case anyone (like me) is thinking - wait did that aeroplane have a parachute? From: https://en.m.wikipedia.org/wiki/Cirrus_Airframe_Parachute_Sy... The Cirrus Airframe Parachute System (CAPS) is a whole-plane ballistic parachute recovery system designed specifically for Cirrus Aircraft's line of general aviation light aircraft including the SR20, SR22 and SF50. The design became the first of its kind to becom…

What are the problems with making such a system for large passenger aircraft (perhaps with multiple parachutes)?

To add to another comment larger planes have much better redundancy (multiple engines, multiple control lines, multiple pilots, etc.) so the situations where a parachute would help are much much fewer. So weight is probably better spent on making the redundant systems even more redundant than anything else.

Re: Midair Collision over Denver

#78

Post by throwaway0a5e »

ordu wrote: post #28
gresrun wrote: post #2

ATC comms with visualization: https://www.youtube.com/watch?v=f5tb2dVWJqc

The pilot is speaking about failed engine after the collision, like it is nothing. Fascinating. I'd be shouting something obscene in such a situation. For half an hour at least, I think.

When people encounter emergency situations in domains they are familiar with they tend to do a pretty good job of rolling with it.

Re: Midair Collision over Denver

#79

Post by throwaway0a5e »

Aeolun wrote: post #72
goodcanadian wrote: post #65

Earlier quoted context omitted.

He might not have been aware of the full extent of the damage. He is on final; the plane is flying; he's lost an engine; he's going to land it. There is no time for anything else.

I think it’s amazing planes can fly sort of straight with only one engine providing thrust though.

He was on final. The engine was providing little more than idle thrust. If he were taking off some serious rudder input would have been required.

Re: Midair Collision over Denver

#80

Post by throw0101a »

vertis wrote: post #75

This[0] youtube video has good explanation with the air traffic control audio. The metroliner pilot was cool as a cucumber after being hit. [0]: https://www.youtube.com/watch?v=_Ph7OR6C90w

See also VASAviation's recreation of radar plot, which is referenced in the above video:

* https://www.youtube.com/watch?v=f5tb2dVWJqc

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